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#ifndef __NET_IP_TUNNELS_H
#define __NET_IP_TUNNELS_H 1
#include <linux/if_tunnel.h>
#include <linux/netdevice.h>
#include <linux/skbuff.h>
#include <linux/socket.h>
#include <linux/types.h>
#include <linux/u64_stats_sync.h>
#include <linux/bitops.h>
#include <net/dsfield.h>
#include <net/gro_cells.h>
#include <net/inet_ecn.h>
#include <net/netns/generic.h>
#include <net/rtnetlink.h>
#include <net/lwtunnel.h>
#include <net/dst_cache.h>
#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#include <net/ip6_fib.h>
#include <net/ip6_route.h>
#endif
/* Keep error state on tunnel for 30 sec */
#define IPTUNNEL_ERR_TIMEO (30*HZ)
/* Used to memset ip_tunnel padding. */
#define IP_TUNNEL_KEY_SIZE offsetofend(struct ip_tunnel_key, tp_dst)
/* Used to memset ipv4 address padding. */
#define IP_TUNNEL_KEY_IPV4_PAD offsetofend(struct ip_tunnel_key, u.ipv4.dst)
#define IP_TUNNEL_KEY_IPV4_PAD_LEN \
(FIELD_SIZEOF(struct ip_tunnel_key, u) - \
FIELD_SIZEOF(struct ip_tunnel_key, u.ipv4))
struct ip_tunnel_key {
__be64 tun_id;
union {
struct {
__be32 src;
__be32 dst;
} ipv4;
struct {
struct in6_addr src;
struct in6_addr dst;
} ipv6;
} u;
__be16 tun_flags;
u8 tos; /* TOS for IPv4, TC for IPv6 */
u8 ttl; /* TTL for IPv4, HL for IPv6 */
__be32 label; /* Flow Label for IPv6 */
__be16 tp_src;
__be16 tp_dst;
};
/* Flags for ip_tunnel_info mode. */
#define IP_TUNNEL_INFO_TX 0x01 /* represents tx tunnel parameters */
#define IP_TUNNEL_INFO_IPV6 0x02 /* key contains IPv6 addresses */
/* Maximum tunnel options length. */
#define IP_TUNNEL_OPTS_MAX \
GENMASK((FIELD_SIZEOF(struct ip_tunnel_info, \
options_len) * BITS_PER_BYTE) - 1, 0)
struct ip_tunnel_info {
struct ip_tunnel_key key;
#ifdef CONFIG_DST_CACHE
struct dst_cache dst_cache;
#endif
u8 options_len;
u8 mode;
};
/* 6rd prefix/relay information */
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel_6rd_parm {
struct in6_addr prefix;
__be32 relay_prefix;
u16 prefixlen;
u16 relay_prefixlen;
};
#endif
struct ip_tunnel_encap {
u16 type;
u16 flags;
__be16 sport;
__be16 dport;
};
struct ip_tunnel_prl_entry {
struct ip_tunnel_prl_entry __rcu *next;
__be32 addr;
u16 flags;
struct rcu_head rcu_head;
};
struct metadata_dst;
struct ip_tunnel {
struct ip_tunnel __rcu *next;
struct hlist_node hash_node;
struct net_device *dev;
struct net *net; /* netns for packet i/o */
unsigned long err_time; /* Time when the last ICMP error
* arrived */
int err_count; /* Number of arrived ICMP errors */
/* These four fields used only by GRE */
u32 i_seqno; /* The last seen seqno */
u32 o_seqno; /* The last output seqno */
int tun_hlen; /* Precalculated header length */
struct dst_cache dst_cache;
struct ip_tunnel_parm parms;
int mlink;
int encap_hlen; /* Encap header length (FOU,GUE) */
int hlen; /* tun_hlen + encap_hlen */
struct ip_tunnel_encap encap;
/* for SIT */
#ifdef CONFIG_IPV6_SIT_6RD
struct ip_tunnel_6rd_parm ip6rd;
#endif
struct ip_tunnel_prl_entry __rcu *prl; /* potential router list */
unsigned int prl_count; /* # of entries in PRL */
int ip_tnl_net_id;
struct gro_cells gro_cells;
bool collect_md;
bool ignore_df;
};
#define TUNNEL_CSUM __cpu_to_be16(0x01)
#define TUNNEL_ROUTING __cpu_to_be16(0x02)
#define TUNNEL_KEY __cpu_to_be16(0x04)
#define TUNNEL_SEQ __cpu_to_be16(0x08)
#define TUNNEL_STRICT __cpu_to_be16(0x10)
#define TUNNEL_REC __cpu_to_be16(0x20)
#define TUNNEL_VERSION __cpu_to_be16(0x40)
#define TUNNEL_NO_KEY __cpu_to_be16(0x80)
#define TUNNEL_DONT_FRAGMENT __cpu_to_be16(0x0100)
#define TUNNEL_OAM __cpu_to_be16(0x0200)
#define TUNNEL_CRIT_OPT __cpu_to_be16(0x0400)
#define TUNNEL_GENEVE_OPT __cpu_to_be16(0x0800)
#define TUNNEL_VXLAN_OPT __cpu_to_be16(0x1000)
#define TUNNEL_NOCACHE __cpu_to_be16(0x2000)
#define TUNNEL_OPTIONS_PRESENT (TUNNEL_GENEVE_OPT | TUNNEL_VXLAN_OPT)
struct tnl_ptk_info {
__be16 flags;
__be16 proto;
__be32 key;
__be32 seq;
int hdr_len;
};
#define PACKET_RCVD 0
#define PACKET_REJECT 1
#define PACKET_NEXT 2
#define IP_TNL_HASH_BITS 7
#define IP_TNL_HASH_SIZE (1 << IP_TNL_HASH_BITS)
struct ip_tunnel_net {
struct net_device *fb_tunnel_dev;
struct hlist_head tunnels[IP_TNL_HASH_SIZE];
struct ip_tunnel __rcu *collect_md_tun;
};
static inline void ip_tunnel_key_init(struct ip_tunnel_key *key,
__be32 saddr, __be32 daddr,
u8 tos, u8 ttl, __be32 label,
__be16 tp_src, __be16 tp_dst,
__be64 tun_id, __be16 tun_flags)
{
key->tun_id = tun_id;
key->u.ipv4.src = saddr;
key->u.ipv4.dst = daddr;
memset((unsigned char *)key + IP_TUNNEL_KEY_IPV4_PAD,
0, IP_TUNNEL_KEY_IPV4_PAD_LEN);
key->tos = tos;
key->ttl = ttl;
key->label = label;
key->tun_flags = tun_flags;
/* For the tunnel types on the top of IPsec, the tp_src and tp_dst of
* the upper tunnel are used.
* E.g: GRE over IPSEC, the tp_src and tp_port are zero.
*/
key->tp_src = tp_src;
key->tp_dst = tp_dst;
/* Clear struct padding. */
if (sizeof(*key) != IP_TUNNEL_KEY_SIZE)
memset((unsigned char *)key + IP_TUNNEL_KEY_SIZE,
0, sizeof(*key) - IP_TUNNEL_KEY_SIZE);
}
static inline bool
ip_tunnel_dst_cache_usable(const struct sk_buff *skb,
const struct ip_tunnel_info *info)
{
if (skb->mark)
return false;
if (!info)
return true;
if (info->key.tun_flags & TUNNEL_NOCACHE)
return false;
return true;
}
static inline unsigned short ip_tunnel_info_af(const struct ip_tunnel_info
*tun_info)
{
return tun_info->mode & IP_TUNNEL_INFO_IPV6 ? AF_INET6 : AF_INET;
}
static inline __be64 key32_to_tunnel_id(__be32 key)
{
#ifdef __BIG_ENDIAN
return (__force __be64)key;
#else
return (__force __be64)((__force u64)key << 32);
#endif
}
/* Returns the least-significant 32 bits of a __be64. */
static inline __be32 tunnel_id_to_key32(__be64 tun_id)
{
#ifdef __BIG_ENDIAN
return (__force __be32)tun_id;
#else
return (__force __be32)((__force u64)tun_id >> 32);
#endif
}
#ifdef CONFIG_INET
int ip_tunnel_init(struct net_device *dev);
void ip_tunnel_uninit(struct net_device *dev);
void ip_tunnel_dellink(struct net_device *dev, struct list_head *head);
struct net *ip_tunnel_get_link_net(const struct net_device *dev);
int ip_tunnel_get_iflink(const struct net_device *dev);
int ip_tunnel_init_net(struct net *net, int ip_tnl_net_id,
struct rtnl_link_ops *ops, char *devname);
void ip_tunnel_delete_net(struct ip_tunnel_net *itn, struct rtnl_link_ops *ops);
void ip_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
const struct iphdr *tnl_params, const u8 protocol);
void ip_md_tunnel_xmit(struct sk_buff *skb, struct net_device *dev,
const u8 proto);
int ip_tunnel_ioctl(struct net_device *dev, struct ip_tunnel_parm *p, int cmd);
int __ip_tunnel_change_mtu(struct net_device *dev, int new_mtu, bool strict);
int ip_tunnel_change_mtu(struct net_device *dev, int new_mtu);
struct rtnl_link_stats64 *ip_tunnel_get_stats64(struct net_device *dev,
struct rtnl_link_stats64 *tot);
struct ip_tunnel *ip_tunnel_lookup(struct ip_tunnel_net *itn,
int link, __be16 flags,
__be32 remote, __be32 local,
__be32 key);
int ip_tunnel_rcv(struct ip_tunnel *tunnel, struct sk_buff *skb,
const struct tnl_ptk_info *tpi, struct metadata_dst *tun_dst,
bool log_ecn_error);
int ip_tunnel_changelink(struct net_device *dev, struct nlattr *tb[],
struct ip_tunnel_parm *p);
int ip_tunnel_newlink(struct net_device *dev, struct nlattr *tb[],
struct ip_tunnel_parm *p);
void ip_tunnel_setup(struct net_device *dev, int net_id);
struct ip_tunnel_encap_ops {
size_t (*encap_hlen)(struct ip_tunnel_e
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